Home |
Search |
Today's Posts |
#1
![]() |
|||
|
|||
![]()
Hi Group, I am entertaining building anohter regen. My first attempt,
although pretty, was a mediocre performer- using a 3 section compactron tube. http://parelectronics.com/pics/regen2.jpg Design goals a 1. plug in coils for band changing MW-20 MHz or so. 2. speaker level audio 3. smooth regen 4. prefer miniature tubes to octal. Anyone care to post their favorite schematic/ links/ thoughts? Tnx, Dale W4OP |
#2
![]() |
|||
|
|||
![]()
Dale Parfitt wrote:
Hi Group, I am entertaining building anohter regen. My first attempt, although pretty, was a mediocre performer- using a 3 section compactron tube. http://parelectronics.com/pics/regen2.jpg Design goals a 1. plug in coils for band changing MW-20 MHz or so. 2. speaker level audio 3. smooth regen 4. prefer miniature tubes to octal. Anyone care to post their favorite schematic/ links/ thoughts? Tnx, Dale W4OP I'm guessing that thats the one from the GE book? I've not built that one but have heard mixed reviews. If you really want to build a stable and manageable kick-butter go regen/superhet. The Regenodyne in its various iterations can be found on the web and is highly recommended. I'm just now winding up another revision of the George Grammar rig from 1941 with some added audio stages. I'm tickled (pun) with it! Another one that is likeable is the ARRL SimpleX Super. I like old stuff and have thoughts of building it with octals and plug-in coils ![]() GL, Bill |
#3
![]() |
|||
|
|||
![]()
"- exray -" wrote in message
... Dale Parfitt wrote: Hi Group, I am entertaining building anohter regen. My first attempt, although pretty, was a mediocre performer- using a 3 section compactron tube. http://parelectronics.com/pics/regen2.jpg Design goals a 1. plug in coils for band changing MW-20 MHz or so. 2. speaker level audio 3. smooth regen 4. prefer miniature tubes to octal. Anyone care to post their favorite schematic/ links/ thoughts? Tnx, Dale W4OP I'm guessing that thats the one from the GE book? I've not built that one but have heard mixed reviews. If you really want to build a stable and manageable kick-butter go regen/superhet. The Regenodyne in its various iterations can be found on the web and is highly recommended. I'm just now winding up another revision of the George Grammar rig from 1941 with some added audio stages. I'm tickled (pun) with it! Another one that is likeable is the ARRL SimpleX Super. I like old stuff and have thoughts of building it with octals and plug-in coils ![]() GL, Bill I have a "Science Fair" Regen receiver here which does the AM broadcast band to 30 mhz. Personally, I think it sucks, but that's my opinion. I acquired the full manual for it and am contemplating putting it up on E-Bay for someone who may like Regens to play with. It "may" need the tuning touched up a bit, but "I" don't have time. It's sat on my shelf for 99.8% of the time I've owned it. C.L.F. |
#4
![]() |
|||
|
|||
![]()
Hi, Gang
I'm thinking of adding a product detector to my HRO-50. I see that Dovetron used to make an adapter that plugged into the NBFM socket. Does anyone have any experience with the Dovetron unit, and can anyone point me to a schematic? BAMA and the ManualMan came up empty. Thanks, Ed Knobloch |
#5
![]() |
|||
|
|||
![]() "Edward Knobloch" wrote in message news:d8fyf.130$C%3.116@trndny03... Hi, Gang I'm thinking of adding a product detector to my HRO-50. I see that Dovetron used to make an adapter that plugged into the NBFM socket. Does anyone have any experience with the Dovetron unit, and can anyone point me to a schematic? BAMA and the ManualMan came up empty. Thanks, Ed Knobloch I have one in a Collins 75A2. It's pretty remarkable. |
#6
![]() |
|||
|
|||
![]()
A few years ago I had a notion to figure out why most kit regenerative
receivers just didn't work, despite their reputation for great sensitivity, bla bla bla. I looked at a few schematics and a few points really jumped out at me. Basically, most standard Heathkit/KnightKit circuits are just Hartley or Armstrong oscillators with variable plate or screen voltage, provided by a potentiometer.. At first this sounds reasonable, but the goal of a regenerative receiver is really that it NOT oscillate. Most of the circuits have 2 fatal flaws, both of which lead to the same result. The 2 flaws are grid-leak bias and resistance coupling to the following audio stage. The problem is that these techniques cause a shift in tube operating points as the signal strength changes, making it "snap" into oscillation. This occurs because any signal, or impulse, or anything else that drives the grid instantaneously positive causes grid current to flow and charges the grid capacitor, biasing the grid negative and reducing the plate current. This wouldn't be so bad except that the reduction in plate current causes the plate voltage to rise, due to the coupling resistor in the plate circuit. As the plate voltage increases the gain increases and the thing snaps into oscillation, ready or not. I put together a test unit using the Armstrong (tickler) circuit, but I used NO grid condenser or resistor. Instead, I returned the grid circuit to a 0-20 volt regulated power supply (properly bypassed for RF, of course)so I could control the grid bias manually. Also used choke coupling, actually the primary of an output transformer in the plate circuit. Used a 6T4, and the circuit would still work even with plate voltages below 30 volts. I didn't fool around with it too much after I proved my point, but the thing really did work pretty well, far better than any "kit" regenerative I have ever seen. With regulated power supplies I could get some real sensitivity and a smooth roll into regeneration. I was impressed. Never did make a real project of it, but it was a good experiment. If you go back and look at some of the pre-historic regenerative circuits you will notice the same concepts at work. Most were choke coupled, and many used variometers or "throttle condensers" to control regeneration. Again, these techniques do not allow the DC operating point of the tube to change with variations in signal strength. Just food for thought. "Dale Parfitt" wrote in message news:Bdeyf.1445$he.1382@trnddc03... Hi Group, I am entertaining building anohter regen. My first attempt, although pretty, was a mediocre performer- using a 3 section compactron tube. http://parelectronics.com/pics/regen2.jpg Design goals a 1. plug in coils for band changing MW-20 MHz or so. 2. speaker level audio 3. smooth regen 4. prefer miniature tubes to octal. Anyone care to post their favorite schematic/ links/ thoughts? Tnx, Dale W4OP |
#7
![]() |
|||
|
|||
![]()
Hi Dale:
I have built a number of regen receivers. One of the great ones is in one of the "How to Become a Radio Amateur" pamphlets. It was also in QST and maybe in some of the Handbooks. It uses 2 x 6AQ5 tubes and can run a speaker directly. Regeneration is controlled by a pot in the screen and it is very smooth. Fits all your requirements. If you need more details, I have the bbok upstairs. I can get the QST date if that helps. 73, Colin K7FM |
#8
![]() |
|||
|
|||
![]() "COLIN LAMB" wrote in message nk.net... Hi Dale: I have built a number of regen receivers. One of the great ones is in one of the "How to Become a Radio Amateur" pamphlets. It was also in QST and maybe in some of the Handbooks. It uses 2 x 6AQ5 tubes and can run a speaker directly. Regeneration is controlled by a pot in the screen and it is very smooth. Fits all your requirements. If you need more details, I have the bbok upstairs. I can get the QST date if that helps. 73, Colin K7FM Hi Colin, Nice to hear from you- if you have a title, and it made it to the Handbook- perhaps I have it in one of the vintage ARRL Handbooks- otherwise, date of the article will be helpful. Dale |
#9
![]() |
|||
|
|||
![]() "COLIN LAMB" wrote in message nk.net... Hi Dale: I have built a number of regen receivers. One of the great ones is in one of the "How to Become a Radio Amateur" pamphlets. It was also in QST and maybe in some of the Handbooks. It uses 2 x 6AQ5 tubes and can run a speaker directly. Regeneration is controlled by a pot in the screen and it is very smooth. Fits all your requirements. If you need more details, I have the bbok upstairs. I can get the QST date if that helps. 73, Colin K7FM Thanks to the WEB, I have found a restoration article on this RX and a note giving its original publication. http://www.antiqueradio.com/Apr01_restoration.html Dale W4OP |
#10
![]() |
|||
|
|||
![]() "Dale Parfitt" wrote in message news:7Phyf.855$MG1.424@trnddc05... "COLIN LAMB" wrote in message nk.net... Hi Dale: I have built a number of regen receivers. One of the great ones is in one of the "How to Become a Radio Amateur" pamphlets. It was also in QST and maybe in some of the Handbooks. It uses 2 x 6AQ5 tubes and can run a speaker directly. Regeneration is controlled by a pot in the screen and it is very smooth. Fits all your requirements. If you need more details, I have the bbok upstairs. I can get the QST date if that helps. 73, Colin K7FM Thanks to the WEB, I have found a restoration article on this RX and a note giving its original publication. http://www.antiqueradio.com/Apr01_restoration.html Dale W4OP The complete construction article also appeared in the 1964 edition of "How to Become A Radio Amateur." Don't know if it ever appeared in the Handbook. I do have a copy of the article, but not handy. If you can wait 10 days or so I can scan it for you. |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
my new mobile install - any thoughts? | Equipment | |||
Stable Regen Receiver--Does it Exist?? | Homebrew | |||
T-Kit 1054 Regen Schematic? | Homebrew | |||
Thoughts on odd behaviour of 10m vertical | Antenna | |||
Initial thoughts on my new 909 | Shortwave |